1. Field of the Invention
This invention relates to a method. More specifically, this invention relates to a method of analysis, and to a test kit for performance of such analysis. The preferred method of analysis of this invention involves the use of a diagnostic test kit specific for the quantitative determination of Human Leukocyte Elastase (HLE) on the plasma membranes of lymphocytes and mononuclear phagocytes as means of monitoring pathologic response of such cells to various disease states.
2. Description of the Prior Art
It is known that Human Leukocyte Elastase (HLE) is co-localized with CD4 and chemokine receptors on the plasma membrane of lymphocytes and mononuclear phagocytes. Human lymphocytes, mononuclear phagocytes, and polymorphonuclear cells derive from lineage-committed pluripotent stem cells along discrete pathways determined in bone marrow. HLE is localized on the plasma membrane early in ontogeny and is granule-localized later in ontogeny suggesting that HLE is an early differentiation marker (Borregaard and Cowland, Granules Of The Human Neutrophilic Polymorphonuclear Leukocyte, Blood, Vol. 89:3503-3521 (1997).
The primary function of cell-surface HLE appears to involve cell motility, and recent evidence suggests modulation of cell-surface HLE dramatically influences cellular response. Although plasma membrane-associated HLE has been previously shown to produce membrane-associated cellular response factors, detection of cell-surface HLE density has not heretofore been recognized as a reliable barometer of, nor utilized to monitor, corresponding pathologic responses, such as the onset or progression of an HIV infection. More specifically, immunochemical interaction of antibodies specific with markers characteristic of cell-surface HLE have been generally unreliable as a measurement of cell-surface density of HLE. The reason for such lack of correlation has up to now been unknown. It has recently been observed that when cells from healthy volunteers are infected in vitro, HIV production is correlated with the cell surface density of HLE, but not to HIV receptors CD4, CXCR4, nor CCR5, (Bristow, C. L., Clin. Diagn. Lab. Immunol., Vol. 8, September 2001.). These recent data indicate that HIV infection is facilitated by co-patching with CD4, CXCR4, and HLE on extensions of the plasma membrane. Accordingly, a primary function for HLE in CD4-related events, appears to include HIV entry and augmentation of immune response.
The conventional method for determining the presence or progression, of a pathologic disease state, generally involves monitoring of certain analytes in specific biological fluids for the presence or absence of the pathogen, or a protein (e.g. antibody) produced by the individuals immune system in response to the presence of the pathogen. Notwithstanding, the availability of such analysis, the extent or progression of a pathologic disease state is not generally ascertainable by such techniques because of the lack of direct quantitation in change in concentration of the pathogens in such assays. Where, as in the case of an HIV infection, the extent of such infection is determined indirectly by analysis of the blood samples for the presence of cells critical to immune response. This type of analytical protocol is of little or any value in the monitoring of seropostive HIV positive individuals who do not express the classical AIDS symptoms, nor is it of value in subtle adjustment in applied therapies in the containment or treatment to prevent the progression of AIDS. Accordingly, there continues to exist a need for a simple and effective diagnostic test to quantitatively measure pathologic disease states, such as an HIV infection, including changes in disease progression, to assist in the prescription of an appropriate therapy, or in the adjustment in the dosage of such therapy. Such diagnostic test, to be effective, should be based upon changes in some parameter, in the basal level of an analyte, which is sensitive to and directly implicated by the pathologic changes associated with different disease states.